I have dug out my colorstar 3000(8 channel version) again to do some colour neg printing and having examined the accessories supplied with it and thoroughly read the manual but I am still puzzled about exactly what probe covers I actually have. The manual in my opinion doesn't describe the covers very clearly.

Spot Measuring: I have the clear spot probe cover which I think requires that part 152 is used at all times. This is the translucent part that is placed over the measuring cell and shaped to fit under the clear top 151.

Am I right in assuming that part 152 is used at all times?

Selective integral measuring: This is listed as part 104. However I seem to have two different types. The first has a white top which is smooth on both surfaces and underneath has an inverted white plastic dome which has an opening of 17mm. This seems to be designed to diffuse the light from the projected negative but only allow the central 17mm portion to reach the measuring cell

The other cover I have has a slightly greyer and darker looking smooth top with an underneath section which is quite rough so the light would be very diffused and this cover has no white plastic inverted dome so all the light from the projected neg will register on the measuring cell. In other words this probe cover is the same size as the other covers(60mm across) but will allow a 60mm section of the neg to be projected through the cover, so a much bigger section of diffused neg is measured(60mm v 17 mm)

Full Integral Measuring: This appears to be provided by a 7cm x7cm sheet of diffusion material which is placed under the lens to give full integral measuring using the clear spot probe cover.

I think I have understood the parts for spot measuring and full integral measuring but I am confused about what the two white covers are designed for and which one (17mm gap on top of inverted white plastic dome or 60mm cover without any plastic dome ) is the appropriate one for selective integral measuring.

I think it has to be the one with the 17mm gap but what is the cover with a smooth/rough diffuser for? I could see no reference to two covers in the manual, just to cover 104.

Hopefully one of our Colorstar 3000 users will be able to clarify matters. Needless to say neither cover has any number on it to help with identification.